Trees are susceptible to damage, disease and decay for many reasons, both natural and man-made. Trees are remarkably resilient and normally do not fail without some warning.
Most structural problems in trees can be identified by adequate visual and technical inspection by a professional arboriculturist.
Ensuring safety and avoiding damage to people or property are, of course, paramount and this can be achieved through a sensible and pragmatic approach that pays due consideration to the benefits of trees.
In most cases of potential hazard, the council will carry out remedial work without removing the whole tree and usually without significant loss of the other benefits that the tree provides.